ROBBIE Williams has performed in some of the world's top venues. And now he is to play a leading role in lectures at a Manchester University.

ROBBIE Williams has performed in some of the world's top venues. And now he is to play a leading role in lectures at a Manchester University.

The pop star won't be there in person but Umist scientists Dr Patrick Gaydecki and Prof Nigel Allinson will explain how he and his chart rivals excite and stimulate our senses.

Prof Allinson will focus on the techniques used in video while Dr Gaydecki will concentrate on the manipulation of sound.

And the pair hopes their insight into the secrets of the pop industry will excite young people enough to consider a career in science.

''What we are trying to do is to get young people interested in a numerical discipline through digital signal processing,'' said Dr Gaydecki, who argues technology can be as important to chart success as having a good voice.

''Lots of music has a wide range of special effects which have come about through digital technology and couldn't have been reproduced 10 or 20 years ago. I'm going to use pop music to show how we can bring about these effects.''

In his lecture on March 20 - Robbie Williams, Old Church Hymns, Signals, Systems and Violins - Dr Gaydecki will demonstrate how voices can be manipulated to sound like they are coming through a telephone and how a recording in a small studio can be made to sound like it's been made in a massive concert hall.

He also intends to prove to young people that their pop heroes may not have the gilded voices they believe them to and may owe as much to their sound equipment as their talent.

And although he plans to put Robbie Williams in the spotlight, he says the former Take That favourite has an excellent voice and uses none of the shame saving techniques he will reveal.

''Robbie Williams is probably my favourite recording artist,'' said Dr Gaydecki. ''I don't know what effects they do use in Robbie Williams' music because I am not privy to the recording studios.

''But what I am quite sure of is Robbie Williams has an excellent voice. You can tell in his music there are not a lot of voice effects. The structure of his music is quite advanced. He is a very clever man and he is one of my favourites.''

But not everybody, he says, in the pop world necessarily has similar levels of talent and skill. ''You can turn anyone into a pop star,'' said Dr Gaydecki.

''Using a computer we can process music to sound quite different. You can make people sound a lot better than they are.

''You can even raise the pitch if someone goes out of tune on a single note.'' During his lecture Dr Gaydecki will outline how digital signal processing computers convert data from the real world, like sound, into number.

''The lecture should be quite spectacular and it will show that maths is not boring,'' he said.

In the second of the two lectures on March 21 ''Video on the Move'' Prof Allinson will outline developments in video that could see visual images travelling down phone lines.

Prof Allinson, professor of image engineering, said: ''Our technology will provide video on mobile phones four or five years before the competition. That's the kind of thing that still excites me about engineering.''

The free lectures have been organised as part of National Science Week and are primarily aimed at schools and colleges. To obtain tickets for the event contact the Umist ticket hotline on 0161-200-4023.